On June 23 in South Africa – making a global impact one of dozens of white wines I recommended was Tesco Finest Darling Sauvignon 2006 (12%) at £6.99. I’ve had several communications from readers reporting that they went to buy it and the shelf was bare. Some of them charitably thought that perhaps my power was so great that the shelves had been stripped the minute my article was published and that they had simply arrived too late. Others were understandably cross that they couldn’t follow my recommendation. Someone in Surrey did find one lonely bottle but when he took...